Lines and other markings (hereafter “markings”) may be applied to surfaces such as driving surfaces for a variety of reasons. For example, solid and/or dashed lines may be drawn along the middle of a roadway to delineate one lane from another. Such lines may indicate various rules of the road, such as when it is permissible to pass other vehicles. Lines may also be drawn in parking lots to demonstrate to visitors where vehicles should be parked.
Markings may be applied to a driving surface using a variety of materials or “binders,” including but not limited to epoxy, thermoplastics, Methyl Methacrylate (“MMA”), and so forth. Some binders may be more viscous than others. For example, some forms of MMA and/or thermoplastic may be viscous enough to be considered “profileable.” A material may be profileable when it is possible to apply the material to a driving surface so that the material retains a profile relative to the surface (e.g., when viewed from the side), rather than spreading across the surface as a less viscous liquid might. Some profileable materials may include sand and/or glass beads to increase profileability/viscosity.
Markings may be applied to a driving surface using a variety of techniques. For example, materials may be sprayed onto a surface using a sprayer. The resulting baseline markings may be fairly uniform; they may not include many “blank” portions or “gaps” through which the underlying surface is visible. Baseline markings also may have a fairly flat profile relative to the surface to which they are being applied. Baselines may typically be applied using materials of relatively low viscosity. Pumping more viscous materials such as profileable material through a sprayer may cause the sprayer head to be damaged quickly and frequently, in turn causing the applied baseline markings to have rough edges. This may be especially true where the profileable binder includes sand or other solid materials. Thus, where clean baseline markings are desired and profileable material is used, it may be necessary to frequently replace damaged sprayer heads.
Markings may be applied to a driving surface in a less uniform matter, such as in a controlled splatter or agglomeration. Unlike baseline markings, a splattered (also referred to as “agglomerated”) marking may not be as uniform when viewed from above, and may include a number of gaps or holes through which the underlying surface is visible. A splattered marking may be applied using profileable binder, resulting in a non-flat or rough profile relative to the surface upon which it is applied. An agglomerated marking may also have less uniform or more rough edges than a baseline.
When using profileable material, in many cases driving surface markings are applied to a surface using a buggy. Buggies typically are not usually much larger than a medium-sized car and typically store profileable material in pressure tanks Pressure tanks may be limited in size by various regulations and practical limitations (e.g., the small size of the buggy). Due to their relatively small size, it may be necessary to stop work and refill pressure tanks frequently. Additionally, static pressurized delivery systems associated with buggies may be dictated by ground speed.
Reflective elements such as glass beads or reflective ceramic elements may be embedded into a marking on a driving surface. The reflective elements may make markings easier to see in the dark because light from horizontally-aligned headlights may be more likely to be reflected from a reflective component embedded in binder. However, embedding relatively large/heavy reflective elements into binder may be challenging. If too much pressure is used to embed the elements into the binder, the binder may be flattened by the impact of the reflective elements or by excess air pressure. If too little pressure is used, on the other hand, the elements may not embed deep enough and may not be retained in the material.